Science-Jazz & Humanism

A short approach to space launchers

– how to build rugged sattelite rockets with medium-size companies

In the near future space access will become one of the most important capabilities of all developing nations in the world. Countries like India, Pakistan, China and Israel have shown historically how space technology can help to establish enduring peace and development in the regions. After long periods of migration, foreign interest and intervention they have finally arrived in a more or less stabile state of decades of dependable preservation and protection of good conditions for growing economy and the development of their countries. Space launchers played an essential role for the fostering of peace by deterrence and driving development of those countries by technology [1].

Introductory Remark

Yesterday I read an article about a container ship that was suspected to smuggle drugs. But the Panamanian officers found rocket parts probably destined for North Korea [46][47]. The subject matter of this article is developing countries by developing space technology. It is meant in the sense of Mahatma Ghandi [48], who advised his people to do all things by themself and not buying things from other countries. This was, why the lawyer Ghandi allways carried a spinning wheel with him as a symbol. The Indians have developed then their own space launchers and satellites up to and including the smallest screw. Therefor they needed their own educated people from their own universities. This article is not about delivering complete weapons and instruction books to empower dictators to threaten other countries by the pushing of a button.

Enduring Peace with Space Technology

Only space access can ensure

surveillance needs to observe troop movements on the planet

ensure peace by deterrence and retaliation capability

The founder of the chair of space technology at Technische Universitaet (Technical University, TU) of Berlin [2], Prof. Eugen Saenger [3], had written a political-philosophical article in 1958 on how to preserve worldwide peace with space technology and surveillance satellites. It’s title was „Raumfahrt – technische Ueberwindung des Krieges“ [4], translated: „Space technology – overcoming of war“. I’m not sure if Saenger had read Imanuel Kant [5], but his book picked up some universal, everlasting valid ideas of Imanuel Kant’s „Perpetual Peace: A Philosophical Sketch“ [6]. Imanuel Kant demands in his book:

„No secret treaty of peace shall be held valid in which there is tacitly reserved matter for a future war“

„No independent states, large or small, shall come under the dominion of another state by inheritance, exchange, purchase, or donation“

„Standing armies shall in time be totally abolished“

„National debts shall not be contracted with a view to the external friction of states“

„No state shall by force interfere with the constitution or government of another state“

„No state shall, during war, permit such acts of hostility which would make mutual confidence in the subsequent peace impossible: such are the employment of assassins (percussores), poisoners (venefici), breach of capitulation, and incitement to treason (perduellio) in the opposing state“

Today Kants text from 1795 is more up to date than ever before, in a globalized world we are living in, where unwanted economic, political, intelligence and military influence on other countries occurs more frequently than in the whole human history and emerges as a steady source of hatred, terror and war.

Points 2 and 5 can be ensured today definitely with space launching systems. Eugen Saenger also thought, that point 3 and in some way point 6 could also be ensured with the use of space technology. Only the contracting aspects of point 1 and 4 would then remain for ensuring perpetual peace.

Like Prof. Saenger I believe deeply in the power of space technology to bring us enduring peace. This can be explained by universal principles first identified and well defined by the great Prussian philosopher Immanuel Kant. I also believe, because of the same principles, that computer networks and automated total observation of all countries will bring us endless hatred, terror and wars. Distrust leads to hate of the people you are not willing to trust and their hate leads finaly to the terror that is distributed by a view of them and this terror leads to war. Who is searching obstinately for terrorist will allways produce more new terrorists. It becomes infamous if he knows about this phenomenon.

I’m very worried about this young former NSA agent [7] who is reputed to became a Paul from a Saul, who spreads informations about insolently stealing any data from all our networks. There is a small possibility that he is executing a well planed function, that his job is to spread hate, to produce new enemies and terrorists, and thereby to secure and enlarge jobs, influence and political power of his agency. But if this is not his function and he is – more probable – only a victim of fate, he produces the new terrorists anyway. In both cases the NSA and it’s methods is responsible for the new terrorists that will definetely emerge now. The difference is only intention or culpable negligence.

Freely accessable Surveilance Sattelites

I wittnessed once, how small selfmade university surveillance satellites became the only free source of information of the overall situation in the Second Gulf War. Military and governmental sources of surveillance [8] were completely unavailable at this time as well as the GPS system was jammed. But there was this small, civilian surveillance system called TUBSAT, build by Prof. Renner [49], one of the folowers of Prof. Saenger. Any journalist in the world had access to it’s surveillance sattelite photographs if he wanted. Even for the journalists of the participating western countries of the Gulf war, the pictures were the only available source of space surveillance information. No foreign intelligence or secret service were able to limit or prevent the distribution of the pictures at that time. Why? Because it is allowed by law to launch your own surveillance satellites! There is no exclusive right for any government or institution in the world. If you can build it, you are allowed to build it and you are allowed to use it and give the surveillance pictures to whoever you want. I don’t know who should have a problem with that, do You?

But it seemed that most of our journalists were afraid to ask for the freely available sattelite surveillance services or – for journalists more worse – didn’t know of the existence of this information source. The big media enterprises who pay most of the journalists salaries which own most of the newspapers and magazines or the big TV channels must be interested in freely available Earth survaillance information. Such sattelites are available for a view million Euros today. Their operation costs in the range of a sallary of one engineer per year plus radio equipment, a little more than on radio amateur level. These satellites can provide joystick controlled high resolution color images of any region in the world. Why do the media enterprises of the world not own hundreds of such small surveillance satellites? On the other hand they are participating on the expensive broadcasting satellites. But they don’t use cheap surveillance sattelites! It seems they don’t need them because they get any information which is allowed them to show.

After the Gulf war and after the lone decision of a slightly confused young US soldier [10], history has shown that it is still common practice to cover and suppress all informations that are painful for the military and governmental leaders. Today, investigative journalism is going to be criticised more and more by a new type of pro-governmental journalist. They don’t need their own means of information procurement, of course. But this is, why we need small civilian surveillance sattelites and the free accessible information they can provide. Civilian surveillance sattelites built and launched by small and medium-size private companies are the consequental continuation of free press photography. Any smaller nation, any oppositional force, any free press needs surveillance sattelites, for witnessing the truth. It has become much to easy to manipulate images that one can rely on foreign sources.

The political and technological Challenge of Launchers

When I was a student, I was fascinated of the idea of developing a small German launching system by means of a large university like TU Berlin. I founded an organisation for that and found some people with the same interests and even a smaller financial source. We startet to develop a small hybrid rocket engine with 1000 N thrust. But we didn’t find by far not enough political support in Germany and had to stop our developments mostly of monetary reasons. No one of relevance wanted to join our idea. So we were not able to finance the necessary redesigns after our first test series, that were partially successful but also showed some mayor design issues that had to be improved. It was a very bad situation for us, because we Germans knew exactly what to do to make our hybrid rocket engine work, but no one in Germany wanted us to do. Later some US companies showed the world how to build big hybrid rocket engines for tourist space ships. We were a little sad that it was not us, to be the first, but also happy, that we had foreseen this aspect of the future absolutely right: that it was possible to build bigger hybrid rocket engines for launching tasks.

On 9/11/2001 [11] we all knew: the short time of technical-intellectual freedom in Germany was over again – the age of intelligence, observation and a secret war against terrorism had begun. We would probably never get the chance to develop free non-governmental commercial space launching systems in our engineer careers. Most of us left the field of space technology, because we did not want to work for governement agencies or big industry enterprises. We wanted to found and build up German medium-size space faring companies. This seemed to be a new adventure. Just doing any space technology for international agencies and global industry, to work in very big entities and to develop small parts in big teams, adopting the groundwork of the old, seemed to be boring, more something for people with a bureaucratic mentality and very uninteresting to most of us.

It is very important to understand: although there were some professors at our institute of aerospace engineering, that were very afraid of colaboration with us, there was no one who forbid or banned our team and our work. This is simply because it was and still is allowed to build civilan space launchers. Any German citizen is allowed to build a civilian space launcher by law! Why should he not? So, any student at any German university is allowed to do so. And exactly for the same reason, because it is allowed by law, any German entrepreneur can also develop space launchers, if he wants to. He can always do exactly the same as Mr. Elon Musk [12] did in the USA with his company SpaceX [13]. What an US company is allowed to, any other company in the world is also allowed to, isn’t it?

But be careful! Once You have worked in a classified military or governmental project, anything is over. Then You can not tell Your oppinions and philosophical thoughts public as I do here. Then You are not allowed to found space companies just as You like, as Mr. Musk did years ago. Anything You say or do then can make You very easily a spy, a traitor, a thief, a criminal. It is very difficult to separate between the knowlege to build classified systems and the general expert knowledge. Therefor most classified people simply stop talking. Anything I have written in the previous paragraph is only valid, if You never work in classified projects! There is absolutely nothing that You can not also know, what people in classified projects know. Mathematics and physics are always the same. An old wise man told me this once.

You can not build such complicated systems only with technical experts and specialists. You also need scientific universalists, who are able to hold the complete system in their minds and are able to transform ideas into hardware. I once met such an engineer, it was the former chief developer of the Saturn rocket system, Prof. H.H. Koelle [14], also a follower of Prof. Eugen Saenger. Prof. Koelle was very impressive, he was a very educated man and was a real universalist. I think he was a genius. To make such complicated systems like space launchers work, one needs free space for such complicated geniuses, too. A free education system is the requirement for the development of such people. They are very rare. The United States didn’t have one single person for a long time who was able to build a simple and cheap rocket system, they urgently needed, until Elon Musk from South Africa entered the scene and just did it. Before him it was H.H. Koelle from Germany who built the first cheap civilian launcher: the Saturn. But it is not only such outstanding individuals that you need for your space launcher development. You also need a good education system in your country which produces well trained people the rare geniuses need for the work to do. And you also need the economical background that makes it possible to build very expensive hardware by very well payed engineers. Mr. Musk was lucky, that he was himself the economical background at his time – he was a millionaire, one of the PayPal founders.

Space launching systems combine most technologies ever invented, this is why countries who develop space launching systems have to invest huge sums into education. You need a university which offers at least:

thermodynamics

heat transfer

gas dynamics

aerothermodynamics

turbo machines and fluid flow engines

cryogenic engineering

combustion

light weight construction

structural dynamics

mechanical engineering

civil engineering or architecture

high temperature materials science

light weight materials science

physical chemistry and pyrotechnics

hydraulic and pneumatic systems

elektric motors and servo systems

power electronics

digital electronics

realtime computer systems

high frequency electronics

signal processing and control theory

sensor technology

prediction filters and sensor fusion

flight dynamics and astrodynamics

navigation

meteorology

Any lack of knowledge of this fields will endanger the functioning of the complete launching system. The needed very wide, interdisciplinary, fundamental scientific knowlege for developing space technology starts a broad spin-off effect for the economy, education, art, aufklarung in your country, because people who study some of this complicated fields must be educated. They read books, and not only technical books. This education leads to demogratic interest of the educated people: the question of codetermination. It is only logical extrapolation to assume that the building of space launching systems and the emerging supplying high-tech industries and universities in new developing countries can stabilize their internal political circumstances and socio-economical developments.

The Energy and Basic Material Wars

Today in some existing (partially) developed countries like Germany, Italy, France, England and USA, we find a general opinion that the energy and basic materials resources on the planet are so strictly limited, that it is not possible to let all seven billian human beings live at American or European wealth standards. Hence the formation of new industry countries with developing space and nuclear technology is seen with envy and much irrational fear. It is the fear of loosing the prosperity standards and anxiety for redistribution of power on the planet.

But we have witnessed exactly the same redistribution in the last ten years. While the United States fought for fossile energy resources in Middle East, China grew up by mostly using nuclear and water power and secured many new basic materials sources in Africa. Today China is just overtaking the United States economicaly. No one could ever prevent nor slow down those developments because of many minor reasons but only one compelling reason: China posesses enough long range space launchers to target any country which would interfere their interiour affairs.

It is true: energy and basic materials sources on the planet are limited. Therefor in the medium-term future it will become essential to get access to the practically unlimited energy and basic materials sources of the solar system we are living in. China has identified this fact and strengthens it’s space efforts. Some naive journalists still believe in an explanation of sole Chinese power demonstration for those efforts. It seems, they don’t know much about Confucian wisdom.

And this is the only reason why China and India are investing into space technology. They are aware of the problem of limited resources on Earth and as relatively peaceful cultures they are searching in time for methods of avoiding future wars for energy and basic materials with the established industry nations. It is not neccessary to fight wars for natural resources on Earth if they are practically unlimited available in the vicinity of Earth.

Observation and Limitation is the wrong way

To make this inevitable space access possible for any smaller nation on planet Earth I have developed a simple space launcher design, that I will introduce now. I had published the design ten years ago for the first time, but I want to pick it up again, and present it here a second time, because of the worldwide historical developments during the last months, where it has been shown again, that the way of global observation, intervention and limitation of development of other countries is the wrong way to prevent terror and war. Vice versa: the last announcements of total observation of any individual that uses modern information technology has produced many times more enemies than ever existed before.

I assume our newest fighting methods by using artificial intelligence and combat robots produces any single day thousands new enemies against the western way of life. Most people on the planet hate us now, because of our modern way of fighting. „Cowardly“ is how boys, men, fighters, warriors call it in other countries. But it is actually exactly the diplomatic phenomenon what Immanual Kant predicted with point 6 of „Perpetual Peace“: acts of hostility which make mutual confidence in the subsequent peace impossible.

Kant didn’t know about the infiltration of computer based information networks with artificial intelligence and the sending of automated combat robots to distant unsecured regions. In his time the cowardly way of fighting was using poiseners (venefici) and assassins (percussores). Today both nasty jobs are automated: the poisener is artificial intelligence which steals and manipulates our information, the assassin is the combat robot which automaticly kills school children [17].

But Kant was not talking about details of cowardice but the interesting phenomenon of mutual confidence that is possible in spite of an ongoing war. It is possible to carefully trust an enemy, if he is following some basic rules. And it is possible to gain peace build on this careful trust coming from this rules. But can You trust governments which infiltrate Your information networks with artificial intelligence rather than asking You about Your oppinions and if not agree send You automated combat robots to fight rather than their sons? I’m sorry, but by no stretch of the imagination I can’t – Immanuel Kant was absolutely right.

We, the North Americans and Europeans, have to stop our information and robot wars immediately to make peace possible and to give other countries and their populations a chance not to hate us. All countries in the world have the natural right to develop, that no one can impede. They must be allowed to develop their own space access and their own nuclear technology fundamentals to ensure their existence and to get a chance for the future securing of energy and raw materials sources in the solar system.

Not so far in the future, in times the resources on Earth become invaluable, any nation that has no access to the moon and the asteroids will perish without any doubt. The Americans knew this once and reached out to the Moon, but forgot and started to use the (more effordless?) way of limitation of other countries. Today the Chinese know about this problem and are planing a moon base [18]. The Indians know about the problem, and some other smaller countries know it, too. They all demand their natural right for development for nuclear technology and for space access. We have to support this international right. But first we have to become aware of this right.

So, why not begin with developing and building a launcher in Germany first to get an exclusive German space access? This would be of manageable risk and for Germany it would be a cheap alternative to the very expensive European ESA space access by using Ariane launchers under French leadership. It is allowed for any country in the world to build their own civilian space launchers. This is international law. And so it is allowed for Germany, too.

The simple Space Launcher

This space launcher design shows a way for developing a system that is as simple as possible but powerful and reliable enough to transport smaller surveillance sattelites into orbit. When mastering the problems of this simple space launcher system a company and it’s country can learn all neccessary technologies for the next steps towards Earth’s Moon and the Asteroid Belt.

The American company SpaceX has proven in the meantime impressively, that it is possible to build space launchers by medium-size companies. When they successfully launched their first Falcon rocket, the company was of amazingly small size! The rocket I will introduce in the next chapter is even simpler than the SpaceX launchers and can be build by a single medium-sized company without a doubt.

The design bases upon rugged Hybrid Rocket technology. It is the same rocket technology that is used by Virgin Galagtic [19] for their very safe tourist space ships. You can also develop Kerosine rocket technology (like SpaceX rockets, or Russian Soyuz [20] rockets) or even liquid Methane rocket engines (like project Morpheus [21] shows successfully). The oxydizer will be in any of the three approaches liquid Oxygen. Methane is liquid at approximately the same temperatures than Oxygen. Kerosene engines are the most simple rocket chambers to develop. Hybrid engines are the safest engines and the only ones you can launch within inhabited regions like Germany. Dont’t use hydrogene fuel technology in Your designs, because experience has shown that this dangerous and unreliable propellant with it’s extremely complicated engines isn’t the way to cheap space travel at all. Hydrogen is technologically interesting but it will be never become a cheap space technology.

The design is a small three stage launcher system that is based on a single clustered LOX/Butadiene [26] engine with 7 metric tons thrust, each. In the first stage 9 hybrid engines are clustered and use a single cubic liquid oxygen tank. On top of the tank are 8 carbon reinforced high pressure vessels that provide the inlet pressure of one single turbopump between tank and hybrid engines. The 9 hybrid engines produce altogether 63 metric tons thrust for lift off. The second stage is realised by four strap on boosters with gas pressure propellant feed systems and together 28 metric tons of thrust. The third stage, that is surrounded by the second stage boosters, uses a single engine with 7 metric tons of thrust and carries it’s own gas pressure feed system, the avionic compartment for the entire rocket, the payload and the payload shroud.

This design is a totaly new approach for using one relatively small engine in three stage rockets. The outstanding element is to use strap on boosters for the second stage and thereby remaining the geometrical proportions for the hypersonic aerodynamics. This would otherwise be very difficult because of the engine number quotient of 9:4:1 which emerges from the mass ratio and thrust requirements. The design bases on the high reliable solid units of the hybrid rocket engines. The burning chambers are actually tire rubber tubes with nozzles at the back end and contain no moving parts, so one can cluster them arbitrary without loosing any system reliability. The liquid, more complicated units of the bundled hybrid engines are united to bigger units wherever it makes sense. There is one big turbopump in the first stage. It makes it possible to run the engines with higher pressure to gain a higher exhaust velocity at sea level. The upper stages don’t need this and gain highest exhaust velocity by area ratio of the nozzles. So a simple but still reliable cluster rocket design emerges. This is new and important, because former low cost cluster rockets had reliability problems. The main advantage of clustering – to develop only one single engine – still remains! A reliable hybrid engine is more difficult to develop than a Kerosine engine, therefor one development has to be enough. When it works you get the safest engine possible that can not explode. Even when the rocket crashes it only burns down until all oxygen is used up. This is an important fact for unexperienced new rocket companies.

Some details of the Rocket Design

The rocket is designed to launch 500kg payload into LEO and was originally thought as a commercial competitor to small civil launcher systems like ESA’s Vega [22], Orbital’s Pegasus [23] and Taurus [24], Cosmos International’s Launcher [25] and even to cheap conversion rockets like Rockot [27] or Dnepr [28]. I will explain now the flight phases of the single stages:

Stage 1 shortly after lift off in 3 km altitude. Below You can see german villages. It is possible to fly above inhabited regions, because a starting hybrid rocket is not more, rather less dangerous for people and environment than a starting jet plane.

Stage 2 in 40km altitude. The first stage has been jettisoned some seconds before. The four strap on boosters, that form the second stage, work. The engine in the middle is still silent.

The big first stage, that we can’t see in the picture anymore, is now falling back on a ballistic trajectory. Slowed down by 3 big parachutes, it will touch down on it’s 9 used ablative cooled nozzles and combustion chambers as destructible dampers (deformable zone). Simple fold-out beams will prevent that the first stage cant’s over after touch down. It will be transported back to the launching facility by a truck and a portable crane and will be refurbished for the next launch within a week.

For refurbishment of the first stage the destructable chambers, nozzles and jet vanes are exchanged with new devices. The turbopump and the oxygen tank as well the pressure vessels are checked and then the pressure vessels will be pressurized again. The refurbished first stage and the new third stage with the four new second stage strap on boosters will be transported to the launching pad by truck and will be assembled on the pad with lifting them by a portable crane. The main connection between the lower and upper part of the rocket is a big pyrotechnic clamp ring. On the launching pad all LOX tanks will be refueled just some hours before lift off.

Stage 3 ignites and accelerates itself and the payload within the next five minutes to orbital velocity. The four strap-on boosters of the second stage have been jettisoned a few seconds before. They fall back and burn while reentering the atmosphere, due to the high velocity the system has reached meanwhile.

Stage 3 jettisons the payload shroud. The shroud falls, like the four second stage strap-on boosters did before, back to earth, e.g. into the sea, a bigger lake or on an uninhabited land region. Because of the much higher flight velocity compared to the first stage, the second stage boosters and the shroud will burn while reentring and can not be reused

Stage 3 after reignition and a second short burning phase in Earth orbit. Within the next seconds the payload, e.g. a smaller surveillance satellite, will be separated. After the payload separation the third stage will reignite again and burn some seconds for deorbiting. Only the payload remains in orbit. Stage 3 is the only stage that can ignite several times. Therefor it uses cold gas nozzles, that are fed from the oxygen gas feed system to accelerate. The acceleration then moves the liquid oxygen back to the suction duct, that the engine can be started. After it’s first long burn that accelerated the 3rd stage to a Hohman [29] trajectory it burns a second time to orbit and a third time to de-orbit.

The third burn is mainly for environmental reasons to prevent space debris. But in principle it makes it also possible, if one develops a kind of a very small, very light „Mercury“ [30] one person return capsule with modern high temperature materials and a carbon reinforced structure of a total maximum of 500 kg weight, to launch one astronaut into space and returning him to Earth after one orbit around the globe. This could be very sensational for Your small country.

The Engine Development

The most important parts of the rocket system are the guidance computer unit, the thrust vector control and the engines. To reduce the effort as much as possible I once have choosen the consequent clustering of one single rocket engine. But I tried to avoid the bad experiences of Lutz Kaysers [31] OTRAG [32] rocket concept and to use all the known results of that time for a totally new approach that is still aplicable for emerging nations.

Looking at the frontside of the 100kN testbed. From the left to the right: the iron pad, the tall chamber, a rocket engineer, the supply platform with 3 oxygen tanks, auxilliary devices, two containers. The engine is exactly the 7 tons thrust engine of the rocket design before.

Pad, supply platform, one already installed and two additional fresh rocket chambers can be transported within two small standard containers. A normal truck with trailer is absolutely sufficient for the transport of the whole development hardware. Whenever a community or administration gets a problem with the engine development, e.g. after the election of a new mayor or a change of a federal state minister, the whole engine development moves on to the next community or federal state or even to another country. Such a flexibility is important for private investors not to be dependend on arbitrary political changes.

The auxilliary devices of the hybrid rocket testbed from the left to the right:

three liquid oxygen tanks for being able to conduct up to three test burnings

butane gas vessel for the ignition mechanism of the hybrid chamber

pressure air vessel for feeding the oxygen

electric generator

compressor for loading the pressure air vessel

kerosene barrel for propelling the electric generator

In this picture you can also see very well the scale of a chamber of 7 tons thrust in relation to a 1,75 m tall person standing in front of it.

The Thrust Vector Control and the Guidance System

Besides the rocket engine the thrust vector control and the guidance of the launcher are the most sensitive components for the overall success of the design. Therefor I have chosen a modified classic jet vane [33] design of the A4(V2) [34], Redstone [35], Pershing [36] and Pershing II [37] missiles for my rocket design. The first stage of the rocket uses 4 jet vanes, each on a corner of the square of the 9-engine-cluster. This gives maximum torque to leave the vanes as small as possible. The second stage has also 4 jet vanes, each is attached on one of the four second stage strap-on boosters. Together they build a cross. Only the third stage uses not 4 but only 3 jet vanes that are attached together on the single engine nozzle. The jet vanes are moved by strong electric standard servos and are controlled via a RS-485 [38] bus. This jet vane system provides very simple full attitude control of roll, pitch and yaw over the complete burn time for each stage.

Thrust Vector Control by Jet Vanes, picture from a projected German Moon lander

The guidance system is built by a common comercial lowly integrated embedded computer with a 180 nanometer (or bigger) radiation hardened 32 bit processor design like an Intel 486 or an early Motorola Power PC. There are actually two boards to develop:

Concept for the avionic system of a German Moon lander demonstrator, a modified version for a launcher is simpler than that for a lander

The first board controls the attitude for any of the flight stages. It uses e.g. 3 Litef [39] fibre optical gyros [40] as sensors, that are connected to the computer via RS-422 [41] or RS-485 [38] serial lines. The gyros are as acurate as necessary to provide full attitude reference for the complete flight time of approximately 20 minutes. The jet vanes for the thrust vector control are controlled via RS-485 bus connection, a serial line that starts in the first stage, just below the payload compartment, where the attitude computer is located, and goes through the second stage boosters and the first stage.

Flight trajectory, height and distance in kilometersDetail of the initial flight trajetory, height and distance in km

The second computer board computes and controls the flight path by integrating the acceleration of e.g. 3 Honeywell [41] high precision acceleration sensors with coordinate transformations using the attitude signal of the first computer. Therefor the processor should have a floating point unit. A Kalman filter [42] predicts the flight path of the integrated acceleration sensors on the fly and merges the position signals of a GPS receiver and a radar height sensor into the prediction loop. This computer can also recalculate and adapt the time based attitude demand on the first attitude control computer due to the Kalman predicted path. This leads to a sufficient accurateness for the orbital point of entry.

Other Rocket Subsystems

The telemetry and abortion signal receiver is realized by off-the shelf senders and receivers. A radar transponder [43] is used. The abortion system is realized by spring valves in the oxidyzer pipes just before the burning chambers. The stage separation system between the first and the second stage is realized by a pyrotechnic clamp ring. The stage separation system of the four second stage strap-on boosters is realized by three pyro-bolts per booster.

The first stage central turbopump is a heavy off-the-shelf high pressure pump that is modified for the use of liquid oxygen as medium. The turbine is a off-the-shelf steam turbine that is directly connected to the pump. The gas generator uses oxygen, kerosene and water to produce the steam for the steam turbine. It is controlled by a processor circuit that is connected via RS-485 to the main computer.

The pressure feed system of the oxygen tanks is regulated by simple mechanical regulators. The pressure gas is Argon or Helium. The pressurization is started by electrical valves. The refuel system for the oxygen tanks is partially manual (fill-up) and electrical (draining, venting).

The separation of the payload shroud is done by one pyro bolt in the nose, one clamp ring between stage and shroud and a pyrotechnical pressured fire hose to separate the two shroud parts, just like the swiss company Contraves [44] has realized it successfully in the Ariane 5 [45] system.

Variants and further Developments

As I mentioned in the beginning, it is not neccessary to develop a complicated hybrid engine. I only have choosen this engine, because it makes it possible to develop and test-flight within inhabited regions like Germany.

If You have more free space in Your country You should start with a much simpler kerosene engine, e.g. with similar thrust level of 7 metric tons. You then should also merge the seven kerosene tanks of the first stage into one single kerosene tank and use a second off-the-shelf pump and off-the shelf steam turbine to provide higher chamber pressure for the 9 first stage engines. The second and third stage would look very similar to the hybrid design. The voluminous hybrid chambers would there become the kerosene tanks and the rocket chambers would be installed at the end. They would also have the large vacuum nozzles to provide sufficient exhaust velocity at a lower chamber pressure, because they would also only use pressure feed systems. For a kerosine design the pressure vessels of all three stages would become nearly as twice as long because of the additional feed gas to provide for the kerosene tank. What You loose in the kerosene design for a second turbopump and bigger pressure vessels You win by a better fuel utilisation to nearly 99%. The complete system is simpler to predict and demands not as much development effort for the engine as the hybrid rocket system.

After you have made first successful orbital flights with Your small kerosene launcher, it is at any time possible for You to allways develop a much bigger kerosene engine and get into much higher payload ranges using the same design. But do not forget: for any doubling of the first stage total thrust You need an additional off-the-shelf turbopump device set. At a thrust of 63 metric tons each, the kerosene engines would have a classical arrangement of two turbopumps on top of each burning chamber. The rocket would then provide a payload of about 4.5 metric tons. You should allways check and calculate if it makes sense to You to further modifying off-the-shelf pumps and steam turbines or rather developing Your own. On higher thrust levels above 63 metric tons per engine You will probably not find suitable off-the-shelf devices anymore and must develop your own turbo-machines. Turbo-machines are very complicated.

You could then also decide to use liquid methane rather than kerosene to get into very high exhaust velocity ranges and thereby further improve engine thrust from 63 metric tons each to around 80 metric tons at approximately the same chamber and nozzle size. The payload of the rocket system would then grow from around 4.5 metric tons to up to 6 metric tons. The methane tanks would become approximately 1.5 times longer than the kerosene tanks at the same fuel mass. But notice that You will become big safety and reliability problems with a second cryogenic propellant. Big cryogenic tanks under mechanical loads can never be completely tight and you have to flush helium gas all the time throughout any single niche of the rocket system to prevent explosions. Never try liquid hydrogen as a fuel, it has the biggest material and technology requirements. The technical problems grow exponentially with the deeper temperatures. Allways start Your developments with kerosene or at the utmost butadiene (rubber) as fuel. Allways use liquid oxygen as the oxidizer.

Investors needed that are brave

As I did ten years before I invite You again to join and to help to develop this very simple but reliable hybrid rocket space launcher system in Germany. First You have to invest some money to build the test stand and to develop the engine. During the engine development the development of the other systems can also start. After the engine works sufficiently the first test flights can begin. The whole development is about 5 years at a cost of about 20 Million Euros including all engine test firings and all partial and as well complete system test flights. This is a realistic value because it is roughly in the range the American company SpaceX also had to spend for the first Falcon rocket.

If You have people that have the skills I mentioned in the list above and are able to develop the launching system by themself You are explicitely allowed to use my rocket design from the point of view of intellectual property. The German laws allow me to own this design I have invited as my intellectual property. But I decided ten years ago, to publish it in the internet and therefor it became automaticly public property. TU Berlin did the same with the components of their micro surveillance sattelites, mostly to prevent protection and forbiddance of intellectual property by others. Please invite me to the first test firings.

There are many people in the world who have the financial power to afford such a technical adventure of 20 million Euros. It is only the worth of one single luxury yacht or one bigger appartment in Monte Carlo. Therefor You can open space for Your home country. But who is brave enough to do what his own country’s laws eventually allow him when having foreign intelligence and influence against him? I did not find such curageous people in Germany until now.

We are one planet and one humanity and anyone has equal rights and must have equal chances and this exactly is our chance. A chance for global development of the human race – together in peace. The chance of tapping endless raw materials and energy sources in the vicinity of Earth. This can only bring us perpetual peace, all other ways will lead into many wars for limited resources, because nations and people want to live free and prosper. The only way out of the dilemma of mankind is space travel for any nation and not limitation and total control. Limitation and control will make it even worser, year by year. One does not have to be a prophet for this prevision, it is simple logic. Leaders of the world: read Immanuel Kant. The Prussian king had read Kant’s books, too. It was a good historical period for my home country.

Resources and explanatory Notes

[1] The opinions and views of the author reflect his own ideas or thoughts and are not based on ideas or opinions or philosophies of the people and institutions mentioned. Certainly their opinions have influenced the authors views, but only the unambiguous positive and constructive aspects of the text. The author is free and does not belong to any of the mentioned institutions or companies.